How big is the Universe
No one knows the size of the Universe. No one can tell how big is the Universe. The Universe has no center. So we can’t measure it. According to Astronomers, the universe is still expanding from the time of the big bank. So Universe cannot be measured, and it is continually expanding.
To measure the size of Universe we would need to calculate the decaying rate of expansion, the distance at which stars move away from each other, and the decaying speed, the speed at which starts travel over the decaying distances. An unknown factor would the volume of matter, as this would also be a determining factor on the speed and distance matter could travel and therefore final size. There may also be something to the spherical space theory. However, this itself begs the question as to what is outside the sphere of space?